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Discussion Starter · #1 ·
I am installing a FASS pump. I went to prime it for the first time and the pump didnt kick on so I tested for voltage at the pump and nothing. fuse is good, I tested the relay and I have power coming in but I dont thing anything coming out. I tried another relay and still nothing. I know the ground on the pump side is good, just no power. The FASS comes with its own harness. including a connector for the old fuel pump and the connector that goes to the old fuel pump.

I cant figure out why I have no power to my FASS.


thanks
 

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Maybe try a jumper wire to bypass the relay for just a second to see if you can get it to come on. Its loud you will easily hear it. Also it will only run for just a couple of seconds when you first turn the key on. When you actually crank the motor is when it will run continuously. I hope its just your second relay was bad or the wires/ connections at that relay are not working/loose. You said you have power coming to the relay, do you know how many volts? I hate that for ya cause the FASS IMO is a great item too have.
 

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Discussion Starter · #3 ·
I have 12.5 volts going to the relay.

why do you need a relay if you have an inline fuse anyway??
 

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The FASS harness does not work on the 05's...you need a key activated hot on spade 85 or 86 not sure off the top of my head...had to wire mine in myself
 

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The relay is what keeps the pump from running constantly. The fuse is just there for overloading protection. I am puzzled too. Have you tried the jumper wire yet? I am worried that the part the relay plugs into is your problem. At least I hope it is. Either way bypass the relay just to see if you can get it to run. If it does run then we know where to focus. I dont think you have a bad pump.
 

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The FASS harness does not have key activated hot coming to the relay...make a jumper from battery to spade 85
 

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Still fighting with FASS on mine 2 yrs later...finally just wired it myself
 

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Discussion Starter · #9 · (Edited)
so positive to 85 and thats it?? I took out the relay and jumped it and still nothing!!
 

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Discussion Starter · #10 ·
do you splice into the wire going to 85? or just not use it and run from battery and replace the 85?
 

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probably won't totally solve the problem because one of the wires on the pump/tank end is not correct...at least that's what i found...mine was actually easier to just wire in my self. Left the stock wiring alone and wired pump with relay in separate. If that's what you decide to do you need constant power to 30, ground to 86, key activated hot to 85, power to pump 87, and then ground the pump separately
 
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You didn't pay hundreds of dollars for the system to wire it in yourself. Something is wrong somewhere. When you jump the relay you have to crank the truck because the truck relays will only keep it hot for a few seconds. Cranking will keep it hot the entire time. You dont have to crank it but key on will only be hot for maybe 2 seconds. What about the module in the tank? is that connection good? I'm sure you've prob checked it but somewhere we are losing power.
 

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Discussion Starter · #13 ·
all my connections are good.

anyone else have this problem??

thanks for all thew help
 

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Where do you live in Ohio? I'm a electrican also & I think you have a bad ground or bad relay if you have the positive wired in the right place. Was this a brand new Fass? Did you put the voltage meter at the pump connector?
 

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Discussion Starter · #15 ·
central ohio. My grounds are good and my relay is to. yes I checked at the pump connector
 
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